Explosive compositions are generally classified as either molecular explosives, heterogeneous explosives or hybrid explosives. A molecular explosive is one in which the essential fuel and oxidizer elements are contained within the same molecule as, for example, in nitroglycerine or trinitrotoluene. A heterogeneous explosive comprises a mixture of separate, small oxidizer and fuel particles, such as in, for example, emulsion explosives. A hybrid explosive comprises a mixture of a molecular explosive and a heterogeneous explosive, such as, for example, nitroglycerine dynamite.
An objective of the explosives industry has been to increase the proportion of the lower cost oxidizer component and decrease the amount of the high cost molecular explosives component in various commercial hybrid explosive compositions. It has also been an objective to find compositions which can replace hybrid explosives without any sacrifice in performance. To a large extent, many of these objectives have been accomplished in recent years by the development of ammonium nitrate/fuel oil blasting agents (ANFO), aqueous ammonium nitrate slurry explosives (U.S. Pat. No. Re. 25,695 --Cook and Farnham), aqueous TNT slurry explosives (U.S. Pat. No. 2,930,685 --Cook and Farnham), water-bearing explosives containing a nitrogen-base salt sensitizer (U.S. Pat. No. 3,431,155 --Dunglinson and Lyerly), ethylene glycol mononitrate slurry explosives (U.S. Pat. No. 3,653,992 --Fee and Hurley), hydroxyalkyl nitrate sensitized explosives (U.S. Pat. No. 3,881,970 --Falconer and Holden) and water-in-oil emulsion explosives (U.S. Pat. No. 3,447,978 --Bluhm). Thus, a wide range of explosives for commercial blasting are now available in a variety of densities, strengths, sensitivities, physical form and price. Existing along side the various above-noted compositions are the conventional stick-type hybrid explosive containing nitroglycerine (NG) or ethylene glycol dinitrate (EGD) as the sensitizer, which explosive type maintains its commercial utility because of its high strength, reliability, sensitivity and competitive cost.
The disadvantages of the so-called NG dynamites lie in hazardous nature of the supersensitive NG or EGD ingredient and the health hazard associated with the vapours given off by these sensitizers. It would be desirable, therefore, if a low cost, safe and non-toxic substitute sensitizer could be found for NG or EGD which substitute sensitizer might also be of use in a wide range of explosive types.
By the practice of this invention, it has become possible to overcome many of the disadvantages and hazards associated with the handling of NG and EGD and to eliminate in whole or in part the need for the use of sensitive molecular explosives in hybrid compositions.
It is, therefore, an object of this invention to provide a novel explosive sensitizer which may be used as the essential sensitizing agent in a wide variety of explosive compositions and, in particular, as a whole or part substitute for NG and EGD in dynamite type compositions.